Fragrance dispenser with user-selectable release rate

ABSTRACT

A fragrance dispenser including at least one receptacle having a major open end, with a porous diffuser layer occlusively overlying the major open end of the receptacle. At least a sectional area of the porous diffuser layer is removable.

BACKGROUND

Fragrance dispensers are often used e.g. to enhance the ambience ofresidences, retail businesses, offices, public areas and so on.

SUMMARY

Herein is disclosed a fragrance dispenser that comprises at least onereceptacle having a major open end, with a porous diffuser layerocclusively overlying the major open end of the at least one receptacle.At least a sectional area of the porous diffuser layer is removable.These and other aspects of the invention will be apparent from thedetailed description below. In no event, however, should this broadsummary be construed to limit the claimable subject matter, whether suchsubject matter is presented in claims in the application as initiallyfiled or in claims that are amended or otherwise presented inprosecution.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a front/side perspective view of an exemplary fragrancedispenser as disclosed herein.

FIG. 2 is an isolated front/side perspective view of an exemplary baseof a fragrance dispenser.

FIG. 3 is a front/side perspective exploded view of an exemplaryfragrance dispenser, with a removable cover sheet omitted.

FIG. 4 is a front/side perspective exploded view of an exemplaryfragrance dispenser.

FIG. 5 is a front plan view of another exemplary fragrance dispenser,with a removable cover sheet omitted and with a porous diffuser layer ofthe dispenser shown laterally exploded away from a base of thedispenser.

FIG. 6 is a front plan view of the exemplary fragrance dispenser of FIG.5, with a one individually removable sectional area having been removed.

FIG. 7 is a front plan view of an exemplary porous diffuser layer asbonded to an exemplary base.

FIG. 8 is a front plan view of an exemplary porous diffuser layershowing a pressure-sensitive adhesive that may be present on a rearsurface of the porous diffuser layer.

FIG. 9 is an isolated side view in generic representation of anexemplary receptacle of a fragrance dispenser, comprising a secondarydiffuser layer, a porous diffuser layer, and a removable cover sheet.

Like reference numbers in the various figures indicate like elements.Some elements may be present in identical or equivalent multiples; insuch cases only one or more representative elements may be designated bya reference number but it will be understood that such reference numbersapply to all such identical elements. Unless otherwise indicated, allfigures and drawings in this document are not to scale and are chosenfor the purpose of illustrating different embodiments of the invention.In particular the dimensions of the various components are depicted inillustrative terms only, and no relationship between the dimensions ofthe various components should be inferred from the drawings, unless soindicated. Although terms such as “top”, bottom”, “upper”, lower”,“under”, “over”, “outward”, “inward”, “up” and “down”, and “first” and“second” may be used in this disclosure, it should be understood thatthose terms are used in their relative sense only unless otherwisenoted.

As used herein as a modifier to a property or attribute, the term“generally”, unless otherwise specifically defined, means that theproperty or attribute would be readily recognizable by a person ofordinary skill but without requiring absolute precision or a perfectmatch (e.g., within +/−20% for quantifiable properties). The term“substantially”, unless otherwise specifically defined, means to a highdegree of approximation (e.g., within +/−10% for quantifiableproperties) but again without requiring absolute precision or a perfectmatch. Terms such as same, equal, uniform, constant, strictly, and thelike, are understood to be within the usual tolerances or measuringerror applicable to the particular circumstance rather than requiringabsolute precision or a perfect match.

The term “front” is used to denote that major side of a fragrancedispenser that comprises a porous diffuser layer bonded thereto. Theterm “rear” is used to denote the opposing major side. These terms areused purely for convenience of description and do not denote ornecessitate any particular configuration in which the dispenser is to bepositioned for use. The term “lateral” as applied to a fragrancedispenser means any direction generally in the major plane of thefragrance dispenser; such directions may often coincide at leastgenerally with a major plane of a diffuser layer that is present in thedispenser.

DETAILED DESCRIPTION

Shown in FIG. 1 in exemplary embodiment is a fragrance dispenser 100.Dispenser 100 may be at least generally rectangular, or may beelliptical, irregular, etc., in overall shape (as defined e.g. by thelateral perimeter of dispenser 100). Dispenser 100 comprises a base 110(shown in isolated view in FIG. 2) with a front side 104 and a rear side102 and comprising at least one receptacle 112 with a major closed end114 and a major open end 116. In some embodiments, base 110 comprises aplurality of (i.e. at least two) receptacles 112 each with a majorclosed end 114 and a major open end 116. Dispenser 100 further comprisesa porous diffuser layer 140 (visible in the exploded view of FIG. 3)that comprises area(s) 143 (most easily seen in FIG. 5) that occlusivelyoverlie the major open end 116 of the receptacle(s) 112. Each receptacle112 and a corresponding area 143 of diffuser layer 140 that overlies thereceptacle 112 combine to define a receptacle volume of that receptacle.A fragrance source 250 (visible in the exploded view of FIG. 3) isdisposed within each receptacle 112. As shown in the exploded view ofFIG. 4, in some embodiments a removable cover sheet 230 may be providedatop diffuser layer 140, which cover sheet may be removed by a user offragrance dispenser 100 when dispenser 100 is to be used.

Base 110 of dispenser 100 may be provided in any suitable manner. Insome embodiments, base 110 may be made of a thermoplastic organicpolymer. Conveniently, in such embodiments the at least one receptacle112 may be provided by forming (e.g., molding, e.g. thermoforming orvacuum-forming) the thermoplastic polymer so as to provide at least onethermoformed depression (as viewed from the front side; such a featurewill be a protrusion as viewed from the rear side) 128 in the base. Insuch an arrangement, a rear terminus of a depression 128 can provide themajor closed end 114 of a receptacle 112 and a major open end of thedepression 128 can provide the major open end 116 of the receptacle. Invarious embodiments, base 110 may be formed from a sheet comprising athickness (e.g. before any areas of the sheet are thermoformed) of fromabout 0.010″ to about 0.40″; in further embodiments, the thickness maybe from about 0.025″ to about 0.030″.

In some embodiments, receptacle 112 may take the form of a shallowcavity or basin as illustrated in exemplary embodiment in FIG. 2. Such ashallow cavity may be significantly wider (along at least one lateraldimension that may be at least generally aligned with a major plane ofthe base) than it is deep (along a dimension at least generallyorthogonal to a major plane of the base). In many embodiments, the majoropen end 116 (which, in use of dispenser 100 after removal of any coversheet, may be unobstructed e.g. except for the presence of an overlyingdiffuser layer 140 and optionally an overlying secondary diffuser layer180 as discussed in detail later herein) may be similar in lateral sizeand area to the largest lateral size and area of receptacle 112 (such anarrangement is shown in exemplary embodiment in FIG. 2). In other words,in such embodiments major open end 116 is not in the form of abottleneck or throat. In specific embodiments, the major open end 116 ofa receptacle may exhibit an area that is at least about 70, 80, 90, or95% of the largest area of the receptacle.

Any number of receptacles (e.g. 1, 2, 3, 4, 5, 6, 8, 10 or more) may beused. In some embodiments, some or all of the receptacles may be atleast generally coplanar with each other. Receptacles may be arranged ina regular array, or in an irregular pattern, as desired. Receptacles mayall be the same shape, or may differ in shape. An individual receptaclemay be e.g. circular, square, triangular, rectangular, or irregular inshape. Individual receptacles may all be the same lateral size, or maydiffer in size. The lateral size of an individual receptacle (as may beestablished e.g. by the lateral size of a thermoformed depression in abase, as discussed below) may be e.g. at least about 4, 10, 15, or 20mm. Such a lateral size may be at most about 40, 35, 30, 25, or 25 mm.(The diameter of a generally circular receptacle, or the equivalentdiameter of a noncircular receptacle, may be used as the lateral size ofthe receptacle.) An individual receptacle may have a depth (from themajor closed end 114 to the major open end 116) of at least about 1, 2,3, 4 or 5 mm. An individual receptacle may have a depth of at most about20, 15, 12, 10, 8, 6 or 4 mm. The number of receptacles, and/or thedepth and lateral size of receptacles, can be chosen to provide thedesired total (cumulative) amount of fragrance to be delivered.Likewise, at least some such parameters (in particular the ratio of thelateral size of receptacles to the depth of receptacles) can be chosen(e.g. in combination with the porosity of diffuser layer 140) to tailorthe rate at which the fragrance is released.

In some embodiments, base 110 may be at least substantially impermeableto volatilizable fragrance. This property may be provided by thematerial of base 110, by a material that provides a layer of base 110,or by several layers of base 110 in combination. By substantiallyimpermeable is meant that the ratio of the rate at which volatilizablefragrance can leave a receptacle by passing through the material of thebase, to the rate at which the volatilizable fragrance can leave thereceptacle by passing through the diffuser layer, is less than 0.001 (at21° C.).

As noted, a porous diffuser layer 140 is positioned (e.g., is attachedto the front side 104 of base 110) so that at least one area 143 ofdiffuser layer 140 occlusively overlies a major open end 116 of at leastone receptacle 112. In some embodiments, at least two areas 143 ofdiffuser layer 140 respectively occlusively overlie the major open ends116 of at least two selected receptacles 112. In this context, toocclusively overlie means that substantially the only way thatvolatilizable fragrance can exit a receptacle 112 is by passing as avapor through (the air-filled passages of) the overlying area 143 ofdiffuser layer 140. In some embodiments, this may be achieved by bonding(by any suitable means, e.g. via adhesive, heat-sealing, ultrasonicwelding, or the like) diffuser layer 140 to one or more bonding areas117 that partially or completely laterally surround the lateral edges124 of receptacle(s) 112. (However, as discussed later herein, it maynot be necessary that a hermetic seal of each individual receptacle 112is achieved.)

Diffuser layer 140 is porous, defined herein as meaning that the layercomprises air-filled passageways (e.g., microperforations, interstitialspaces between fibers, interconnected air-filled cells of an open-celledfoam, and the like) that extend completely through the diffuser layerfrom one major surface to another. (It is not necessary, however, thatthe passageways extend through the layer in a straight line, or alongthe shortest distance between the major surfaces.) Such air-filledpassages allow the passage of volatilized molecules therethrough invapor form. Porous diffuser layer 140 will be distinguished from a layerthat does not comprise porosity (i.e., a layer in which a smallmolecule, in order to pass through the layer, must solubilize in thesolid material of the layer and then move therethrough by moleculardiffusion through the solid material, rather than passing throughair-filled passageways).

In at least some embodiments, diffuser layer 140 may be at leastsubstantially impermeable to liquids along any dimension thereof. Such adiffuser layer 140, while allowing fragrance molecules in vapor form topass therethrough so as to exit receptacle(s) 112, may not allow anyflow of liquid fragrance (or the liquid form of any other materialpresent in fragrance source 250) e.g. through the thickness of diffuserlayer 140 so as to permit the material to escape receptacles 112 inliquid form. In particular embodiments, diffuser layer 140 may not allowany liquid to flow (e.g., by wicking due to capillary action) along themajor plane of diffuser layer 140. A porous diffuser layer 140 of thistype will be distinguished from e.g. wicking layers and the like thatare often used e.g. to facilitate the movement of a liquid through thewicking layer to a location in which the liquid can be evaporated and/orto spread the liquid over a wider area so that is can be more rapidlyevaporated.

Porous diffuser layer 140 may be conveniently provided as a sheet asshown in exemplary embodiment in FIGS. 3 and 5. Such a sheet may be afilm (e.g., a microperforated film, with a microperforation being athrough-hole having an average diameter of 400 microns or less), aknitted or woven material, etc. In particular embodiments, diffuserlayer 140 is a nonwoven sheet (web). Such a sheet may thus comprise anumber of specific through-holes that pass directly through thethickness of the sheet (e.g. in the case of a microperforated film); or,a sheet (e.g. a nonwoven) may comprise tortuous paths (e.g., definedcollectively by numerous fibers) through the thickness dimensionthereof. Either arrangement (or any combination thereof) may be used aslong as the ability to permit passage of vapors therethrough (and theability to deny flow of liquids therethrough, if desired) is achieved.It will be appreciated that the size (e.g., diameter or effectivediameter for circular or non-circular microperforations) or effectivesize of air-filled passages, as well as the chemical composition of thematerial of diffuser layer 140, may be chosen to achieve the desiredcombination of properties. Surface treatments and the like may be usedto modify e.g. the surface energy of the microperforations, or of fibersthat define a tortuous path, to similar ends.

In particular embodiments, a diffuser layer 140 may be hydrophobic, e.g.by virtue of the composition of the material(s) that makes up thediffuser layer, by virtue of surface treatment, coating or the like thatis provided on at least some surfaces of the diffuser layer, or by somecombination of these. Such a property may render the diffuser layerresistant to being penetrated e.g. by hydrophilic liquid components of afragrance source 250 that is in the form of e.g. an aqueous gel.Similarly, in some embodiments, a diffuser layer 140 may be oleophobic(again either through the composition of the material that makes up thediffuser layer, by a surface treatment or coating, or the like). Such aproperty may render the diffuser layer resistant to being penetratede.g. by hydrophobic liquid components of a fragrance source that is inthe form of e.g. an oil-based gel.

The microperforation size (and/or the effective size of a tortuous path)and/or density of microperforations/paths per unit area of diffuserlayer 140 may be tailored to provide a desirable fragrance release rate.Exemplary perforation sizes of microperforated films may be e.g. fromabout 10 to about 100 microns in diameter (or equivalent diameter in thecase of non-circular or irregular microperforations). A nonwoven orwoven diffuser layer 140 may be optimized e.g. by controlling fiberdiameter, basis weight and solidity and/or thickness, to achieve thedesired properties. Such nonwovens may be produced by different methods,such as spunbonds, meltblown, airlaying, wetlaying (e.g. paper-makingmethods), composite methods such as spunbond-meltblown-spunbond (SMS),and so on. Film materials and/or fibers of a woven or nonwoven fibrouslayer may be chosen from any suitable material, e.g. polyolefins such aspolyethylene and polypropylene, polyvinyl chloride, polyester,polyurethane, cellulosics, and so on. In at least some embodiments,diffuser layer 140 is not a rupturable membrane that is configured to beruptured to initiate the release of fragrance therethrough. Potentiallysuitable materials may be chosen from e.g. materials available fromMidwest Filtration (Cincinnati, Ohio) under the trade designationUNITHERM.

The ability of a porous diffuser layer 140 to allow passage of gases andvapors through the interstitial spaces thereof in order to completelypass through the thickness of the layer, may be characterized by anysuitable parameter or test method. One convenient screening measurementthat may correlate with the ability of a material to serve as a porousdiffuser layer 140 is an air permeability test (a “Frazier” test) asperformed using equipment of the general type supplied by the FrazierPrecision Instrument Company (Hagerstown, Md.). Such testing may beperformed in general accordance with the methods outlined in ASTM TestMethod D737-04 (2012), using 0.5 inches of water pressure drop, a 2.75inch diameter opening and an 11 mm or 16 mm orifice. In variousembodiments, porous diffuser layer 140 may exhibit an air permeabilityof at least about 100, 200 or 300 cubic feet per minute per square foot.In further embodiments, porous diffuser layer 140 may exhibit an airpermeability of at most about 800, 600, 500, or 400 cubic feet perminute per square foot.

Potentially suitable candidate diffuser layers may be tested for theiractual release of fragrance, e.g. using a representative fragrancecompounded in a suitable nonvolatilizable carrier and loaded intoreceptacles of a dispenser to which is attached the diffuser layer. Thedispenser can be held in a controlled environment, e.g. at 21° C. (or ata higher temperature (e.g. 55° C.) for accelerated testing) and theamount and rate of weight loss from the receptacles can be monitored.

As evident in the exemplary arrangement of FIG. 5, in some embodimentsporous diffuser layer 140 comprises a plurality of individuallyremovable sectional areas (e.g., 150 a-f) each of which respectivelyocclusively overlies at least a portion of a major open end 116 of theat least one receptacle (e.g., of any of receptacles 112 a-f). In otherwords, an individually removable sectional area 150 will at leastpartially coincide with a respective area 143 (as previously describedherein) that occlusively overlies a major open end 116 of a receptacle112.

At least selected sectional areas 150 of porous diffuser layer 140 areindividually removable from the remaining areas (e.g. area 163) ofporous diffuser layer 140 (remaining areas 163 may remain in place onbase 110 after removal of one or more areas 150). Removal of a selectedarea 150 thus serves to uncover at least a portion of a major open end116 of a receptacle 112 that the selected sectional area occlusivelyoverlay prior to its removal. By “uncover” is meant that volatilizablefragrance emitted from that portion of receptacle 112 no longer has topass through porous diffuser layer 140 to escape dispenser 100; it doesnot require that the portion of receptacle 112 no longer has any layeroverlying it. For example, as discussed in detail later herein, in someembodiments a secondary diffuser 180 may be present through whichfragrance still has to pass even though the fragrance does not have topass through porous diffuser layer 140. Moreover, the act of uncoveringa major open end of a receptacle does not require that the entire areaof the open end must be completely uncovered (in other words, aremovable area 150 does not necessarily have to coincide with theentirety of a respective area 143).

The act of removing a selected area 150 from porous diffuser layer 140will create an opening in the area of porous diffuser layer 140 formerlyoccupied by the selected area, through which volatilizable fragrance cannow pass at a rate that is not limited by porous diffuser layer 140. Insome embodiments selected areas 150 are removed by being completelyphysically separated from the remaining areas of porous diffuser layer140. However, in other embodiments a selected area 150 may merely beseparated from remaining areas of porous diffuser layer 140 e.g. alongseveral sides of the selected area 150, and may remain connected to atleast one remaining area of porous diffuser layer 140 (e.g. by afrangible connection as discussed below). The concept of a “removable”area thus does not require that the removable area must necessarily becompletely physically separated from the remaining area of porousdiffuser layer 140 in the act of removing the area, although in someembodiments this can be done.

It will be appreciated that the arrangements presented herein allow thatone or more selected sectional areas can be individually removed fromthe porous diffuser layer to uncover at least a portion of a receptaclethat the selected sectional area formerly occlusively overlay, withoutuncovering any portions of other receptacles. For example, withreference to FIG. 5, any one of sectional areas 150 a-150 f may beremoved from remaining areas (e.g. area 163) of porous diffuser layer140 so as to respectively uncover a corresponding receptacle ofreceptacles 112 a-112 f, without uncovering any of receptacles 112 a-112f whose overlying sectional area of porous diffuser layer 140 was notremoved. Any combination of selected areas may likewise be removed. Forexample, areas 150 a and 150 b may be removed, thus uncoveringreceptacles 112 a and 112 b (which again, only requires that at leastportions of the open ends of these receptacles be uncovered), whileleaving areas 150 c-150 f in place occlusively overlying receptacles 112c-112 f.

It will be appreciated that removing any or all of sectional areas 150from porous diffuser layer 140 can accelerate the rate of emission ofvolatilizable fragrance from the receptacle(s) that the sectionalarea(s) formerly overlay. Any number of individually removable sectionalareas, overlying any corresponding number of major open ends ofreceptacles, may be provided. For example, one, two, three, four, five,six, seven, eight, nine, or ten or more sectional areas (andcorresponding receptacles) may be provided (six individually removablesectional areas 150 a-150 f and six corresponding receptacles 112 a-112f are shown in the exemplary embodiment of FIG. 5).

Major open end 116 of each receptacle 112 exhibits an area. In variousembodiments, a corresponding removable sectional area 150 that overliesat least a portion of the major open end of the receptacle, may beconfigured so that removal of the sectional area of the porous diffuserlayer uncovers from about 10% to about 100% of the area of the majoropen end of the receptacle. This can allow an increased rate of emissionof fragrance from that particular receptacle, while not allowingaccelerated emission of fragrance from any other receptacle that has notbeen uncovered. As mentioned above, it is not necessary that the entirearea of an open end be uncovered in the act of removing a sectional area150, although this can be done if desired. In some embodiments,sectional areas 150 may be configured so that their removal uncovers atleast about 20, 40, 60, or 80% of the area of the major open end of thereceptacles that they respectively overlie. In further embodiments,sectional areas 150 may be configured so that their removal uncovers atmost about 100, 90, 80, 70, 60, or 50% of the area of the major open endof the receptacles that they respectively overlie. It is not necessarythat all of the sectional areas must be identically sized (nor is itnecessary that all of the receptacles are identically sized), nor is itnecessary that any portion of a removable sectional area is exactlycentered over a receptacle, although any of these can be done (as in theexemplary embodiment of FIG. 5) if desired.

Thus in some embodiments, different sectional areas 140 may be ofdifferent sizes. In some embodiments, dispenser 100 may includeinstructions for use. In some embodiments such instructions may beprovided on a separate document that is packaged with the dispenser, orwhich may be printed on the packaging. In some embodiments suchinstructions may be virtual instructions resident on a website to whichthe user is directed. In some embodiments such instructions may take theform of at least one indicia that is provided on a component ofdispenser 100 (e.g., that is printed on a major surface of the base, theporous diffuser layer, or the removable cover sheet). Such indicia e.g.point out the removable sectional area(s) of the porous diffuser layerto a user, and/or may guide the user to remove a smaller sectional areaand/or fewer sectional areas in the event that a slight increase in theemission rate of fragrance is desired, or to remove a larger sectionalarea and/or a greater number of sectional areas in the event that alarger increase in the emission rate of fragrance is desired.

In some embodiments, sectional areas 150 are frangibly connected toremaining areas 163 (and, if desired, to other sectional areas 150) ofporous diffuser layer 140 in order that they be removable (e.g.,manually removable by a user). Thus in some embodiments individuallyremovable sectional areas 150 of porous diffuser layer 140 may be (whendispenser 100 is supplied to a user) connected to remaining areas 163 ofporous diffuser layer 140 by frangible connections that are provided bydie cuts 153 that extend through the entire thickness of porous diffuserlayer 140 except at periodic bridging locations 156 where the die cutsare interrupted to provide frangible bridges 155 between the sectionalareas 150 of porous diffuser layer 140 and remaining areas 163 of porousdiffuser layer 140. In some embodiments, die cuts 153 may beconveniently formed in the same act as the die cutting that is performedto generate external edges 157 that define the lateral perimeter andoverall shape of porous diffuser layer 140. In other embodiments, diecuts 153 may be generated in a separate action from the die cutting thatdefines the overall edges of porous diffuser layer 140.

As noted above, in some embodiments at least some periodic bridginglocations 154 may be between adjacent edges of individually removablesectional areas 150 of the porous diffuser layer. One such bridginglocation is shown as location 156 in FIG. 5. Such arrangements may allowe.g. one sectional area to be removed while leaving an adjacent area toremain in place (to be removed later if desired).

In some embodiments, at least selected removable sectional areas 150 mayexhibit a major central portion that is e.g. at least generally centeredover a major open end of a receptacle, and may further exhibit one ormore tab portions 152 (as depicted in FIG. 5) that extend away from themajor central portion. Such tab portions 152 may extend toward aneighboring removable sectional area and if desired neighboring tabportions may meet to provide a bridging location 156 as described above.By such arrangements individual areas 150 may be removed singly; or,several such areas (e.g. an entire strip comprising areas 150 a-150 c)may be removed in a single operation, e.g. without ever separating theindividual areas from each other.

In some embodiments, at least one removable sectional area 150 maycomprise a tab portion (e.g. area 158 of FIG. 5) that at least slightlyprotrudes laterally outward past other portions of porous diffuser layer140, or is otherwise made readily accessible to being grasped by a userof dispenser 100. Such a protruding portion can provide a fingerliftsuch that a first area to be initially removed (e.g. area 150 a of FIG.5) can be easily grasped.

In some embodiments, one or more individual sectional areas 150 may beremoved from porous diffuser layer 140 by being completely physicallyseparated therefrom (and subsequently disposed or recycled). However, itis not necessary that this be done. Thus, in some embodiments a removedsectional area 150 may be left still connected to a remaining area ofporous diffuser layer 140. All that is needed is that the area 150 ismoved sufficiently that it no longer acts to limit the passage ofvolatilizable fragrance out of the uncovered area of the receptacle. Inother words, an area 150 may be peeled away to uncover at least aportion of a receptacle and left e.g. “hanging” from an edge of theopening created by the act of removing the selected area. Such anarrangement in is shown in exemplary embodiment in FIG. 6 in whichindividually removable sectional area 150 c has been removed (peeledforwardly) to the position indicated by 150 c′.

Porous diffuser layer 140 may be bonded to base 110 (e.g. to front side140 of main body 111 thereof) in any manner that will allow sectionalareas 150 to be removed from layer 140. In some embodiments, this may beperformed at least in part by the use of ultrasonic bonds 162 as shownin exemplary embodiment in FIG. 7. In some embodiments such bonds mayextend continuously e.g. along the perimeter of main body 111 of base110 and corresponding areas of porous diffuser layer 140. In otherembodiments (e.g. as in the exemplary arrangement of FIG. 7) such bondsmay be discontinuous. In some embodiments such bonds may be providedaround the perimeter only (again as in FIG. 7); in other embodiments,such bonds may also be present in an interior area of the dispenser(e.g. between row of areas 143 d-f and row of areas 143 a-c of FIG. 5).In some embodiments, such bonding may be performed at least in part bythe use of a pressure-sensitive adhesive (PSA). Such a PSA may act toenhance the bonding of porous diffuser layer 140 to base 110; or, it maye.g. serve primarily to hold porous diffuser layer 140 in place in theproper position on base 110 until another bonding operation (e.g.ultrasonic bonding) provides the final bond. Such a PSA may be providedat any suitable location. In the exemplary embodiment of FIG. 8, a PSAis provided in the form of two stripes 161 that each extend along aperimeter edge of porous diffuser layer 140, and another stripe 161 thatextends along a central portion of layer 140 (e.g. between rows 143 d-fand 143 a-c of FIG. 5). All such PSA's will be on the rear surface 141of porous diffuser layer 140 to facilitate bonding to front side 104 ofbase 110. (Of course, if desired such a PSA could be initially mountedon front side 104 of base 110 rather than on rear surface 141 of layer140.) In various embodiments, a PSA may be applied (e.g. as a preformedstrip of double-faced adhesive, often referred to as a transfer tape) torear surface 141 of porous diffuser layer 140 or to front side 104 ofbase 110; or, a PSA may be formed in place (e.g. by drop-wise digitaldispensing, roll coating, hot melt coating, etc. of a PSA precursor) ona desired surface, prior to mating diffuser layer 140 with base 110.

It will be appreciated that it may not be necessary that porous diffuserlayer 140 (and e.g. any removable cover sheet 230) must be bonded tobase 110 to provide a hermetic seal of individual receptacles 112,although this can be done if desired. Rather, all that is needed is thatany leakage pathway left by a non-hermetic seal should be sufficientlysmall that any loss of volatilizable fragrance from receptacles 112should be minimal during any initial storage period prior to use ofdispenser 100 (e.g., prior to a removable cover sheet 230 being removedto initiate dispensing of fragrance). It has been found that e.g. anon-hermetic combination of PSA and ultrasonic bonding cansatisfactorily meet these conditions.

In some embodiments, dispenser 100 may comprise at least one secondarydiffuser layer 180. As shown in exemplary embodiment in FIG. 9, asecondary diffuser layer 180, if present, may be sandwiched betweenporous diffuser layer 140 and base 110. Secondary diffuser layer 180comprises at least a portion (an area) 181 that is positioned rearwardof porous diffuser layer 140 and overlies a receptacle 112. With thisarrangement, if a sectional area 150 of porous diffuser layer 140 isremoved from a particular receptacle as described above (with coversheet 230 already having been removed), portion 181 of secondarydiffuser layer 180 will be exposed. (In such embodiments, removal ofarea 150 results in the particular receptacle being “uncovered” asdescribed above, even though portion 181 of secondary diffuser layer 180will be in the diffusion pathway of the fragrance that is emitted fromthat receptacle.)

By definition, secondary diffuser layer 180 is more permeable to passageof fragrance therethrough than is porous diffuser layer 140.Specifically, secondary diffuser layer 180 will allow a rate of emissionof fragrance from a receptacle 112 that is at least 50% greater thanthat allowed by the porous diffuser layer 140 (at 21° C.) with which thesecondary diffuser layer 180 is used. In further embodiments, secondarydiffuser layer 180 will allow an emission rate that is at least 100%,150%, or 200% greater than that allowed by the porous diffuser layer140. In some embodiments, individual secondary diffuser layers 180 maybe provided for individual receptacles 112. However, it may beconvenient that a single secondary diffuser layer 180 be used thatincludes various portions (areas) that each occlusively overlie areceptacle 112.

A secondary diffuser layer may serve any desired function. In someembodiments, a secondary diffuser layer may limit the rate of emissionof fragrance from a receptacle 112, below that which would be allowed inthe complete absence of any diffuser layer. In addition to, or insteadof this function, a secondary diffuser layer may serve as a physicalbarrier (but one that is vapor-permeable) to protect fragrance source250 e.g. from being disturbed, dislodged, or contacted. In addition to,or instead of, either of the above functions, a secondary diffuser layermay serve a decorative or aesthetic function (e.g. to provide lessvisual contrast upon removal of an area 150 of porous diffuser layer140). The vapor permeability of secondary diffuser layer 180 may thus bechosen as desired. In some embodiments layer 180 may be comprised of avery open structure (e.g. a very low basis weight nonwoven or scrim, ora polymeric netting or screen) that primarily serves as a physicalbarrier that does not significantly limit the rate of emission offragrance from a receptacle. If desired, a secondary diffuser layer 180may be selected or treated to be at least substantially impermeable toliquids (even while being vapor-permeable) in similar manner asdescribed for porous diffuser layer 140.

In various embodiments, secondary diffuser layer 180 may be chosen frome.g. nonwoven organic polymeric webs, woven or knitted organic polymericmeshes, and organic polymeric nettings or screens. Secondary diffuserlayer 180, if present, may be attached to front side 104 of base 110(and may have porous diffuser layer 140 attached thereto) by anysuitable means or mechanism, e.g. by way of PSAs, ultrasonic bonds, andso on.

In some embodiments, a multilayer stack comprising more than onesecondary diffuser (e.g. of differing vapor-permeability) may bepresent. Successive diffuser layers may thus be removed (e.g. peeledoff, e.g. starting with porous diffuser layer 140) to achieve a desiredrate of emission of fragrance.

In some embodiments, a fragrance dispenser 100 as supplied to a user maycomprise a removable cover sheet 230 that overlies the porous diffuserlayer 140 at least in the areas where diffuser layer 140 overlies thereceptacle(s) 112. In at least some embodiments cover sheet 230 may beimpermeable in order to minimize or prevent any emission of fragrancefrom fragrance source(s) 150 until dispenser 100 is ready to be used, atwhich time cover sheet 230 may be removed and disposed or recycled. Byimpermeable is meant that removable cover sheet 230 comprises at leastone layer of material that provides (or, comprises layers thatcollectively provide) that sheet 230 is at least substantiallyimpermeable to volatilizable fragrance. By this is meant that the ratioof the rate at which volatilizable fragrance can leave a receptacle bypassing through layer 230 (when layer 230 is in place so as toocclusively overlie the receptacle), to the rate at which thevolatilizable fragrance can leave the one receptacle by passing throughdiffuser layer 140 in the absence of layer 230, is less than 0.001 (at21° C.). Any suitable material that is sufficiently vapor-impermeable(e.g. polyester film) may be used.

In some embodiments, a single cover sheet 230 may be provided (e.g. inthe general manner exemplified in FIG. 4) that can be removed as a unitto initiate the emission of fragrance from all of the receptacles 112.Cover sheet 230 may be removably bonded to diffuser layer 140 in anysuitable way that allows at least portions (areas) of cover sheet 230(or the entirety of cover sheet 230) to be removed by a user (e.g., tobe peeled away from diffuser layer 140) to expose porous diffuser layer140 to initiate the emission of fragrance from one or more receptacles112 of dispenser 100. In some exemplary embodiments, rear surface 231 ofcover sheet 230 may comprise a pressure-sensitive adhesive (e.g., aremovable or repositionable PSA) disposed thereon, that allows rearsurface 231 of cover sheet 230 to be removably bonded to front surface142 of diffuser layer 140.

In some embodiments, cover sheet 230 may comprise portions (areas) thatare frangibly connected to remaining portions of the cover sheet so thatselected portions of cover sheet 230 are each individually removablefrom the remainder of cover sheet 230. This can allow a user to uncovera particular sectional area of diffuser layer 140 that occlusivelyoverlies a selected receptacle so as to initiate emission of thefragrance from that selected receptacle without initiating emission offragrance from other receptacles from which overlying portions of coversheet 230 have not been removed. A user can thus successively removeindividual portions of cover sheet 230 (e.g. over hours, days or weeks)to sequentially initiate the emission of fragrance from additionalreceptacles. In a slight variation of such approaches, two separate,individually-removable cover sheets 230 (e.g., one covering areas 143d-f of porous diffuser layer 140, one covering areas 143 a-c of porousdiffuser layer 140) can be used. It will be evident that such operationsare in addition to the above-described sequential removal of selectedsectional areas of porous diffuser layer 140 and can further enhance thedynamic range of user-selectable release rates of fragrance fromdispenser 100.

In some embodiments, (e.g. in the event that dispenser 100 is suppliedsealed within a vapor-impermeable package) cover sheet 230 may notnecessarily serve to seal receptacles 112 to prevent emission offragrance therefrom. In such embodiments cover sheet 230 may e.g. serveprimarily to protect porous diffuser layer 140 from physical damage,and/or may serve a decorative function. In such cases, cover sheet 230may be made of any suitable material.

Fragrance source 250 may include any suitable volatilizable fragrance orany combination of two or more fragrances. Such a fragrance may bechosen to impart a pleasing odor, to mask odors that are perceived asundesirable, and so on. A volatilizable fragrance may be any molecule ormixture of different molecules that is chosen to impart a pleasing odor,to may mask odors that are perceived as undesirable, and so on. Any suchmolecule may be chosen from those compounds commonly referred to asperfumes, aroma compounds, aromatherapy compounds, odorants, flavors,essential oils, and so on. Such molecules will exhibit the appropriatevapor pressure at the temperatures usually encountered in e.g.residential HVAC systems (e.g., 18-25° C.) to function as desired. Invarious embodiments, a volatilizable fragrance may comprise a molecularweight (of a single molecule) or an average molecular weight (formixtures of molecules of different molecular weights), of less thanabout 500, 400, 300, or 200. Various volatilizable fragrances andcategories thereof are disclosed in U.S. Pat. No. 8,043,606 to MacBeath,which is incorporated by reference herein. Potentially suitablefragrances are available e.g. from International Flavors and Fragrances(New York City, N.Y.) and J&E Sozio Descollonges SAS (Paris, France). Inparticular embodiments in which an array of receptacles 112 is present,different fragrances and/or mixtures thereof may be present in thevarious receptacles, as desired.

In some embodiments, fragrance source 250 may comprise one or morevolatilizable fragrances as neat fragrance liquids unmixed with anyother material. (It is noted however that many fragrances may themselvesbe mixtures of numerous molecules.) In many embodiments, however it maybe convenient to mix the at least one volatilizable fragrance with atleast one nonvolatilizable carrier material (with the termnonvolatilizable meaning that in use of fragrance dispenser 100, theratio of the rate at which the carrier material exits a receptaclethrough the diffuser layer to the rate at which the volatilizablefragrance exits, is less than 0.001.)

A nonvolatilizable carrier material may be chosen from any suitablematerial. In various embodiments, such a carrier material may comprisean organic polymeric material (which, in this context, includes e.g.waxes, oils, etc. as long as such materials provide acceptableproperties). Such a carrier material may advantageously provide thatfragrance source 250 is in the form of a viscous liquid, gel, grease,jelly, semi-solid, wax, or the like (noting that there may notnecessarily be a firm dividing line between some of these categories),in the typical temperature ranges at which the fragrance dispenser isused. (The latter temperatures are often in the range of those found ina typical conditioned space; e.g. between 18 and 25° C.)

In further detail, a nonvolatilizable carrier (e.g., a polymericmaterial) may provide a matrix for dispersal of the fragrance thereinto.In some embodiments, the at least one volatilizable fragrance and the atleast one nonvolatilizable carrier material may be mixed with each otherto form a solution (i.e., so that substantially no parcels ofnon-dissolved volatilizable fragrance are present). Exemplary organicpolymers that may find use as nonvolatilizable carriers include e.g.olefinic copolymers, e.g. copolymers of polyethylene with ethylenemethyl acrylate (for example the resins available from Exxon Mobil underthe trade designations OPTEMA 120 and 220), ethylene vinyl acetate(EVA), or other copolymers containing other functional groups such asacids, esters, amides, acrylates, and the like. In addition, the organicpolymer system could be comprised of styrene-isoprene-styrene segmentsor styrene-butadiene-styrene segments such as those seen in Kratonthermoplastic elastomer systems. Fragrance source 250 may comprise(either instead of, or in addition to, any nonvolatilizable organicpolymer that may be present) any suitable inorganic material such ase.g. clay, fumed silica, diatomaceous earth, silica aerogels, and so on.

Fragrance source 250 may also comprise any other agent as desired tochange the viscosity, tackiness or any other characteristic of thefragrance source. (Such agents may be nonvolatilizable orvolatilizable.) Viscosity modifiers include plasticizers such asisopropyl myristate, heavy naphthenic oils, or other polymeric systemsthat may be branched, linear, dendritic, and so on. Tackifiers includeWingtack Plus and the like. If desired, one or more gelling agents maybe used, e.g. wax esters such as those available from Croda, Edison,N.J. under the trade designation SYNCROWAX, and acrylate containingpolymers, such as those available from Air Products, Allentown, Pa.under the trade designation INTELLIMER. Such components may be used toprovide e.g. an oil-based gel. In some embodiments, gelling agents suchas e.g. crosslinked polysaccharides, starches, alginates, carrageenan,and the like, may be used to provide a fragrance source in the form ofan aqueous or aqueous-containing gel. Any fragrance source may of coursecomprise any desired combination of hydrophobic and hydrophiliccomponents, for any purpose, as desired. Components of a fragrancesource 250 may be chosen so as to render the volatilizable fragrancecompletely mixed (e.g., solubilized) with the other components withoutany partitioning or phase separation, and also to prevent or minimizeany syneresis of liquid fragrance (or any other component) therefrom. Insome embodiments, volatilizable fragrance may be provided in an aqueouscarrier, which term generally encompasses solutions of fragrance inwater or in mixtures or solutions of water with other diluents (e.g.alcohols, glycol ethers, and so on), which solutions may further includee.g. additives such as gelling agents, viscosifiers, and so on. Invarious embodiments, fragrance source 250 may exhibit a viscosity at 25°C. of at least about 10, 20, 40, 80, 200, 400, 1000, or 2000 Poise.

In some embodiments, fragrance source 250 may comprise at least onecolorant (e.g., dye). A colorant may be volatilizable (e.g. guaiazulenedye) e.g. with an evaporation rate similar to that of the volatilizablefragrance, so that release of the dye from the fragrance source causes acolor change in the fragrance source that is commensurate with thedepletion of fragrance from the fragrance course. Or, a colorant may benonvolatilizable, and the nonvolatilizable colorant, the volatilizablefragrance, and e.g. the nonvolatilizable carrier material may be chosenin combination so that release of the fragrance from the fragrancesource causes the color of the fragrance source to change so thatdepletion of the fragrance from the fragrance source can be monitored.In either case, at least a portion of base 110 that defines a majorclosed end 114 of a receptacle 112 may be at least translucent ortransparent, so that any change in color of the fragrance source may bevisually observed through the base.

The volatilizable fragrance can be combined with the nonvolatilizablecarrier material (and with any other component) in any desired ratio. Invarious embodiments, the volatilizable fragrance may comprise at leastabout 30, 50, 60, 70, 80, or 90 wt. % of the fragrance source. Infurther embodiments, the volatilizable fragrance may comprise at mostabout 90, 80, 70, 60, 50, or 40 wt. % of the fragrance source. Thefragrance may be combined with other components, e.g. a nonvolatilizablecarrier, by batch mixing, by compounding in an extruder, or in generalby any process that sufficiently disperses or homogenizes the fragrancewithin the matrix. The compounded mixture may be loaded into areceptacle or receptacles to therein provide a fragrance source. Ifdesired, the compounded mixture may be heated slightly to facilitateloading of the mixture into a receptacle.

In some embodiments, fragrance source 250 may occupy at least about 70,80, 90, 95, or 98 volume percent of the receptacle volume, thereceptacle volume being defined in combination by the open-endedreceptacle 112 (e.g., by the downstream surfaces of the moldeddepression 128) and the overlying diffuser layer 140. In specificembodiments, at least a portion of a downstream major surface offragrance source 250 is in intimate contact with an upstream surface ofdiffuser layer 140. In some embodiments, the receptacle may include aspace-filling network of solid material (e.g. an open-cell foam, areticulated foam, a nonwoven, a netting, a collection of particulates orthe like) that is not solubilizable by the liquid fragrance and thatoccupies a portion of the receptacle volume and comprises numerousopen-ended cavities that may collectively provide a reservoir for thefragrance source. If desired, a fragrance source may be pre-loaded intoa space-filling network, which network is then placed into a receptacle112 that is sized and shaped to accept the space-filling network.Exemplary foams may be constructed out of polyethylene, polyurethane,PVC and the like. Exemplary nonwovens and particulates may be those thatare manufactured to be sorbents, such as those manufactured for chemicalspill clean up, e.g., 3M Petroleum Sorbent pads available from 3MCompany, St. Paul, Minn. In at least some embodiments, fragrance source250 as provided in receptacle 112, is not contained within any kind ofsecondary container or barrier, in particular a rupturable barrier,within receptacle 112.

It will thus be appreciated that fragrance source 250 can encompass anydesired method of providing volatilizable fragrance within a receptacle112. In some embodiments, fragrance source 250 may take the form of aflowable liquid, e.g. a neat liquid fragrance. In some embodiments,volatilizable fragrance may be e.g. compounded with a carrier so as tobe present in a receptacle 112 in the form of a generally solid (at 21°C.) mass (e.g., a wafer or puck of any desired shape and aspect ratio).It will be appreciated that this may allow the most freedom to positiondispenser 100 in any desired orientation (e.g. vertical) withoutencountering any possibility of any component (e.g. a liquid component)of the fragrance source inadvertently leaking out of a receptacle. (Suchconsiderations may of course be largely moot in embodiments in whichporous diffuser layer 140 (and/or secondary diffuser layer 180 ifpresent) is impermeable to passage of liquids therethrough.)

It is emphasized that a “fragrance” as referred to herein is a molecule(or mixture of molecules) that is chosen for the specific purpose ofimparting a pleasing odor to an ambient environment or maskingundesirable odors in such an environment. In other words, a moleculedoes not qualify as a fragrance as disclosed herein, merely because itmay exhibit a discernable odor that is incidental to the properties anduse of the molecule. By way of specific example, an isopropylalcohol-impregnated dressing for medical use would not qualify as afragrance as disclosed herein. Similarly, a pouch or sachet that such analcohol-containing dressing is packaged in, would not qualify as afragrance dispenser as disclosed herein.

It is also emphasized that terms such as “volatilizable” and“volatilized” are used broadly to denote that fragrance that is emittedfrom a fragrance source 250 moves (e.g. through any or all of a porousdiffuser layer 140, a secondary diffuser layer 180, and/or an emptyairspace formerly occupied by a porous diffuser layer) as molecules invapor form, rather than in liquid or solid form (e.g. in the form ofaerosol droplets, sprayed liquid or solid particles, and so on). Theparticular process by which the fragrance is liberated from fragrancesource 250 is not limited and may include e.g. evaporation, sublimation,or a mixture of the two. Still further, although the term “diffuser”layer has been used for convenience of description, this does not implythat the passage of a fragrance out of a fragrance source 250 and awayfrom dispenser 100 must occur strictly by molecular diffusion (e.g.,Fickian diffusion). While such a mechanism may operate at least in parte.g. during passage of fragrance through interstitial air spaces of aporous layer, such a mechanism is not required to be the only mechanismby which fragrance is emitted from dispenser 100. In fact, in someembodiments molecular diffusion may not be the primary mechanism, e.g.it may be dominated by some other mechanism. For example, the rate ofemission of fragrance from fragrance source 250 may be significantlyincreased in the event that dispenser 100 is exposed to airflow, incomparison to the emission rate when dispenser 100 is positioned inquiescent air.

It will be appreciated based on the disclosures herein that providingporous diffuser layer 140 with multiple sectional areas 150 that areindividually removable from remaining areas of layer 140, cansignificantly enhance the ability of the rate of release of fragrancefrom dispenser 100 to be selected and customized as desired by a user.This is particularly advantageous in view of the fact that humans haveany ability to smell different substances over a very wide dynamic rangeand that the ability to perceive an odor is subject to habituation. Thisbeing the case, the preferred level of fragrance (as achieved byemitting fragrance at a desired rate from a dispenser) may vary verywidely between different persons. In the present work it has been foundthat providing a porous diffuser layer 140 with multiple individuallyremovable sectional areas as disclosed herein can advantageously allowthe release rate of fragrance to be varied over a wide range.

For example, one user may simply remove cover sheet 230 (in itsentirety) to initiate the emission of fragrance, while leaving porousdiffuser layer 140 in its as-supplied condition (that is, withoutremoving any of the individually removable sectional areas 150 over thelifetime of the dispenser). Another user may likewise remove cover sheet230 in its entirety and may also remove one or more of the individualsectional areas of porous diffuser layer 140 to accelerate the emissionof fragrance from one or more selected receptacles. Such a user mighte.g. remove individual sectional areas at regular intervals (e.g., oneper day, one per week, etc.) in order to achieve a desired rate ofemission of fragrance. Still another user may (after removing the coversheet) initially remove half of the individual sectional areas of porousdiffuser layer 140 and may then remove the remaining individualsectional areas after a given time interval. Another user may remove thecover sheet and immediately remove all of the individual sectional areasof porous diffuser layer 140 thus achieving the highest possible releaserate of fragrance. It is evident that a wide variety of individualpreferences can be accommodated.

Moreover, the above examples have concerned embodiments in which therate of emission of fragrance can be accelerated (by removing individualsectional areas of diffuser layer 140) above a “baseline” rate thatexists when all of the receptacles are emitting fragrance throughdiffuser layer 140. As disclosed earlier herein, the rate of emission offragrance can, if desired, be manipulated to be below this “baseline”rate, by the use of a cover sheet 230 that is itself removable inportions rather than being removable only its entirety. That is, ratherthan the entire cover sheet 230 being removed at initial use ofdispenser 100, in some embodiments only selected portions of the coversheet may be removed to initiate emission of fragrance from thecorresponding receptacles. Additional portions of the cover sheet may beremoved at desired time intervals. It will be appreciated that sucharrangements can further enhance the dynamic range of the rate at whichfragrance can be dispensed by dispenser 100, which can further enhancethe ability to tailor the performance of the dispenser as desired byparticular individuals.

Fragrance dispenser 100 may be used to emit fragrance into an ambientenvironment, in any suitable location. Some uses may involve exposingthe dispenser to a stream of moving air (e.g. as motivated by a fan orblower), as discussed in detail below. Other uses may involve placingthe dispenser in an ambient environment that does not involve a streamof moving air (other than e.g. stray air currents, wind, and so on). Forexample, a dispenser may simply be placed in a room (e.g. hungvertically from a wall, laid flat on a shelf, etc.), a vehicle, and soon. In particular embodiments a dispenser may be positioned in a window(e.g. attached to a window screen) to take advantage of wind impingingthereon.

In some embodiments, dispenser 100 may be itself moved through air (e.g.quiescent air). For example, a dispenser 100 may be mounted to a bladeor hub of a fan (e.g. a ceiling fan), mounted to a door that is openedand closed frequently, mounted to a floor-cleaning robot or a vacuumcleaner, and so on. It is thus apparent that in such embodiments,dispenser 100 may be mounted to any item that can be moved relative tosurrounding air.

In some embodiments, a dispenser 100 may be exposed to a stream ofmoving air that is motivated by a fan or blower rather than by e.g.wind. It is not necessary that the dispenser actually be physicallylocated anywhere near the fan or blower. For example, in someembodiments a dispenser 100 may be positioned proximate an air-emittingvent of a vehicle climate-control system or a building HVAC system. (Forexample, a dispenser could be attached to a register, grille or louverof such a vent.) Or, a dispenser may be positioned proximate an intake(air-return) unit of a building HVAC system (recognizing that in such acase the fragrance emitted from the dispenser will be distributedthroughout the entire portion of the building that is served by the HVACsystem rather than e.g. remaining primarily in one room). A dispensercould be placed in the flowpath of a fan (e.g. a window fan, a box fan,an oscillating fan, a ceiling fan, and so on) e.g. by being attached toa protective grille or casing of the fan or by being mounted to asurface (e.g. of a ceiling, floor, wall, table, shelf, stand, etc.) nearthe fan. Similarly, a dispenser could be placed in the airflow path of aso-called mini-split climate control unit.

It will be appreciated that the rate of emission of fragrance fromdispenser 100 may be affected by the velocity and/or volumetric flowrateof air that impinges on the dispenser and may also be affected bytemperature. This being the case, the procedures disclosed herein may bemodified when dispenser 100 is positioned (e.g. in the summer) in astream of cooled air of an HVAC system, in comparison to the proceduresused when dispenser 100 is positioned (e.g. in the winter) in a streamof heated air from the HVAC system. In some embodiments, the temperatureof flowing air that impinges on the dispenser may be purposefullymanipulated to affect the rate of emission of fragrance from thedispenser. Similarly, one or more heat sources or cooling sources thatdo not involve flowing air (e.g. a miniaturized resistive heater, an IRheater, and so on) may be positioned near dispenser 100 to desirablyaffect the rate of emission of fragrance therefrom.

In some embodiments, a dispenser 100 may be positioned in proximity to(e.g., mounted on) an air filter e.g. of an HVAC unit. In particularembodiments, dispenser 100 may be mounted upstream of such an airfilter, e.g. with a “front” face of the dispenser facing toward the airfilter. Such uses are described in detail in PCT InternationalPublication No. WO 2016011038 and in corresponding U.S. ProvisionalPatent Application No. 62/026,112 entitled FRAGRANCE DISPENSER FOR AIRFILTER, both of which are incorporated by reference in their entiretyherein.

A dispenser 100 may be mounted on an air filter by way of any suitablemechanism. Many such mechanisms may conveniently make use of a perimeterframe of the air filter (such as made from cardboard, chipboard or thelike) for such mounting. In some embodiments base 110 of dispenser 100may thus comprise a main body 111 that comprises the at least onereceptacle 112; and, an extended portion 130 (as shown in exemplaryembodiment in FIG. 2, and omitted for clarity in FIGS. 5 and 6) thatextends away from the main body. Extended portion 130 may comprise anysuitable mounting mechanism configured to mount (attach) to a perimeterframe of an air filter so as to position fragrance dispenser 100 e.g. sothat at least some receptacles 112 thereof are proximate anairstream-receiving or airstream-emitting area of the air filter.

In some embodiments, an extended portion 130 may comprisepressure-sensitive adhesive to facilitate attachment of dispenser 100 toany desired object or surface. Instead of or as an adjunct to anadhesive, extended portion 130 may comprise any mechanicalmounting/attachment mechanism. For example, a small hole may be providedin extended portion 130 of base 110 of dispenser 100, into which anysuitable hook or post can be inserted. It will be understood that thisis merely an example and that many mounting attachment systems may beused.

In some embodiments, an extended portion 130 of base 110 may generallycomprise an L-shape with a first portion that extends from the main bodyof base 110 in a direction at least generally along a major plane of themain body of the base, and a second portion that extends from a terminusof the first portion and that is oriented at least generallyorthogonally to the first portion.

In some embodiments, an extended portion 130 may comprise first andsecond portions as described above, and may further comprise a thirdportion that extends from a terminus of the second portion and thatcomprises a major plane that is oriented at least generally parallel toa major plane of the first portion. Such an extended portion 130 maythus generally comprise a U-shaped hook that allows dispenser 100 to behung from any desired object. Of course, similar arrangements may beachieved e.g. with a hook provided by a smoothly arcuate extendedportion 130 rather than a U-shaped extended portion 130. Althoughextended portion 130 and L-shaped and U-shaped variations thereof weredescribed above with particular regard to mounting dispenser 100 to e.g.a frame of a framed air filter, it will be appreciated any such extendedportion 130 may be used to mount dispenser 100 to any desired object.Furthermore, it will be appreciated that in some embodiments no extendedportion 130 need be present.

In some embodiments, a cover (e.g. a molded plastic cover) may bemounted on the front side of dispenser 100. Such a cover may have e.g.one or more movable (e.g. slidable) portions that can be moved back andforth so as to allow or prevent the emission of volatilizable fragrancefrom various receptacles. Such a cover may e.g. act as an adjunct to theherein-described removable sectional areas of porous diffuser layer 140and/or removable portions of a cover sheet 230, in allowing thedispensing rate of fragrance to be customized by a user. For example, inparticular embodiments in which different fragrances are present indifferent receptacles, such a cover can allow a user to switch back andforth between fragrances that are dispensed.

Dispenser 100 may be produced in any desired manner. For example, afragrance source 250 may be produced by compounding a volatilizableliquid fragrance (which, as noted, may be comprised of a mixture orsolution of many different molecules) with a nonvolatilizable carrier,e.g. at elevated temperature. The resulting mixture may then be loadedinto individual receptacles 112 of base 110 (and, if loaded at elevatedtemperature, may then be allowed to cool, e.g. to form a solid wafer). Asecondary diffuser layer 180 may be optionally bonded to the front side104 of main body 111 of base 110 if desired. A porous diffuser layer 140is bonded to the front side 104 of main body 111 of base 110 (or to thefront side of secondary diffuser layer 180 if a layer 180 is present andif it e.g. extends as far toward the perimeter of the base as does layer140). In various embodiments, such bonding may be facilitated by apressure-sensitive adhesive (PSA) that is disposed on bonding areas ofmajor rear surface 141 of layer 140; such bonding may be by way ofultrasonic bonding; or, a combination of both may be used. A removablecover sheet 230 may be removably bonded (e.g. by way of a PSA) to thefront surface 142 of porous diffuser layer 140. In some embodiments,cover sheet 230 may be bonded to porous diffuser layer 140 before eitherof these components is bonded to the main body of the base. Such anapproach allows layers 230 and 140 to be pre-laminated to each other sothat they can be bonded to the base as a single unit. (In such a case,if porous diffuser layer 140 is to be ultrasonically bonded to the base,the composition of cover sheet 230 may be chosen so that ultrasonicenergy can be transmitted through layer 230 without damaging layer 230).In embodiments in which a secondary diffuser layer 180 is to be present,layer 180 and layers 140 and 230 can all be laminated together to form athree-layer pre-laminated stack that can be bonded to base 110 as aunit, if desired.

Once produced, dispenser 100 can be packaged in any suitable package. Inparticular embodiments the packaging material may be chosen (e.g., thepackaging material may be a metallized polyester) to provide a sealedpackage from which minimal loss of fragrance may occur even overlong-term storage and/or exposure to elevated temperatures. In someembodiments in which dispenser 100 is packaged (i.e. sealed) within apackaging material with appropriate vapor-barrier properties, coversheet 230 may not need to exhibit significant vapor-barrier properties;in particular embodiments of this type, cover sheet 230 may be omittedfrom dispenser 100.

List of Exemplary Embodiments

Embodiment 1 is a fragrance dispenser comprising: a base comprising atleast one receptacle with a major closed end and a major open end; aporous diffuser layer comprising at least one sectional area thatocclusively overlies at least a portion of a major open end of areceptacle; and, a fragrance source provided within at least a portionof the at least one receptacle and that comprises at least onevolatilizable fragrance, wherein the at least one sectional area of theporous diffuser layer is removable from remaining portions of the porousdiffuser layer to uncover at least a portion of a receptacle that the atleast one sectional area occlusively overlies.

Embodiment 2 is the fragrance dispenser of embodiment 1 wherein theporous diffuser layer is an organic polymeric nonwoven web that exhibitsan air permeability of from about 200 to about 800 cubic feet per minuteper square foot.

Embodiment 3 is the fragrance dispenser of any of embodiments 1-2wherein the porous diffuser layer is permeable to vapors but is at leastsubstantially impermeable to liquids.

Embodiment 4 is the fragrance dispenser of any of embodiments 1-3wherein the porous diffuser layer is bonded to the base by apressure-sensitive adhesive that is provided along portions of aperimeter of the porous diffuser layer, and by discrete ultrasonic weldsthat are provided along portions of the perimeter of the porous diffuserlayer.

Embodiment 5 is the fragrance dispenser of any of embodiments 1-4further comprising a secondary diffuser layer that: is at least 50% morepermeable to passage of fragrance therethrough than is the porousdiffuser layer; does not comprise any removable sectional areas; and issandwiched between the porous diffuser layer and the base, wherein theporous diffuser layer and the secondary diffuser layer are configured sothat upon removal of a sectional area of the porous diffuser layer, aportion of the secondary diffuser layer that overlies a receptacle ofthe base is exposed.

Embodiment 6 is the fragrance dispenser of embodiment 5 wherein thesecondary diffuser layer is chosen from the group consisting of anonwoven organic polymeric web, a woven or knitted organic polymericmesh, and an organic polymeric netting or screen.

Embodiment 7 is the fragrance dispenser of any of embodiments 1-6wherein the base is made of a thermoplastic organic polymeric resin thatis at least substantially impermeable to liquids and vapors and whereineach receptacle is provided by a thermoformed depression in the base,wherein a terminus of the depression provides the major closed end ofthe receptacle and wherein a major open end of the depression providesthe major open end of the receptacle.

Embodiment 8 is the fragrance dispenser of any of embodiments 1-7wherein the base comprises a main body that comprises the at least onereceptacle and wherein the base further comprises an extended portionthat extends away from the main body and that comprises a mountingmechanism.

Embodiment 9 is the fragrance dispenser of any of embodiments 1-8wherein the fragrance source is chosen from the group consisting of neatliquid fragrance, liquid fragrance mixed with a nonvolatilizable diluentliquid, liquid fragrance in aqueous solution, and a liquid fragrancesorbed into interstices of a porous insoluble solid matrix material.

Embodiment 10 is the fragrance dispenser of any of embodiments 1-9wherein the fragrance source is a liquid fragrance that is mixed andsolubilized with a nonvolatilizable matrix material that is a solid atroom temperature and that is solublizable by the liquid fragrance, andwherein the fragrance-matrix mixture is in the form of a solid waferwhen at 21° C.

Embodiment 11 is the fragrance dispenser of any of embodiments 1-10wherein the liquid fragrance makes up at least about 80 wt. % of thefragrance source.

Embodiment 12 is the fragrance dispenser of any of embodiments 1-11comprising: a base comprising a plurality of receptacles each with amajor closed end and a major open end; a porous diffuser layercomprising sectional areas each of which occlusively overlies at least aportion of a major open end of a receptacle of the plurality ofreceptacles; and, a fragrance source provided within at least a portionof each receptacle and that comprises at least one volatilizablefragrance, wherein at least selected sectional areas of the porousdiffuser layer are each individually removable from the porous diffuserlayer to uncover at least a portion of a receptacle that the selectedsectional area occlusively overlies.

Embodiment 13 is the fragrance dispenser of embodiment 12 wherein thebase comprises at least six receptacles and wherein the porous diffuserlayer comprises at least six sectional areas that respectivelyocclusively overlie at least a portion of a major open end of each ofthe six receptacles, which six sectional areas are each frangiblyconnected to remaining areas of the porous diffuser layer so that thesix sectional areas are each individually removable from the porousdiffuser layer.

Embodiment 14 is the fragrance dispenser of any of embodiments 12-13wherein the major open end of each receptacle exhibits an area andwherein a sectional area of the porous diffuser layer that isindividually removable from the porous diffuser layer, is configured sothat removal of the sectional area of the porous diffuser layer uncoversfrom about 10% to about 100% of the area of the major open end of thereceptacle that the sectional area of the porous diffuser layerocclusively overlies so as to allow accelerated emission of fragrancefrom that receptacle, while not allowing accelerated emission offragrance from any other receptacle.

Embodiment 15 is the fragrance dispenser of any of embodiments 12-14wherein the major open end of each receptacle exhibits an area andwherein a sectional area of the porous diffuser layer that isindividually removable from the porous diffuser layer, is configured sothat removal of the sectional area of the porous diffuser layer uncoversfrom about 40% to about 60% of the area of the major open end of thereceptacle that the sectional area of the porous diffuser layerocclusively overlies.

Embodiment 16 is the fragrance dispenser of any of embodiments 12-15wherein the individually removable sectional areas of the porousdiffuser layer are frangibly connected to remaining areas of the porousdiffuser layer by frangible connections that are provided by die cutsthat extend through the entire thickness of the porous diffuser layerexcept at periodic bridging locations where the die cuts are interruptedto provide frangible bridges between the individually removablesectional areas of the porous diffuser layer and the remaining areas ofthe porous diffuser layer.

Embodiment 17 is the fragrance dispenser of embodiment 16 wherein atleast some of the periodic bridging locations are between adjacent edgesof individually removable sectional areas of the porous diffuser layer.

Embodiment 18 is the fragrance dispenser of any of embodiments 12-17further comprising a removable cover sheet that overlies, and isremovably adhesively bonded to, the porous diffuser layer; and, thatcomprises at least selected portions that are peelably detachable fromthe porous diffuser layer to expose the porous diffuser layer toinitiate dispensing of the fragrance.

Embodiment 19 is the fragrance dispenser of embodiment 18 wherein atleast selected portions of the removable cover sheet are frangiblyconnected to remaining portions of the removable cover sheet so that theselected portions of the cover sheet are each individually removablefrom remaining portions of the removable cover sheet to uncover aselected sectional area of the porous diffuser layer that occlusivelyoverlies a selected receptacle to initiate dispensing of the fragrancefrom that selected receptacle without initiating dispensing of fragrancefrom other receptacles.

Embodiment 20 is the fragrance dispenser of any of embodiments 18-19wherein the dispenser comprises at least one indicia printed on a majorsurface of the base, of the porous diffuser layer, or of the removablecover sheet.

Embodiment 21 is a method of dispensing fragrance into an atmosphere,the method comprising: positioning a fragrance dispenser of any ofembodiments 1-20 in the atmosphere; if a removable cover sheet ispresent, removing at least a selected portion of the removable coversheet from the fragrance dispenser; and, optionally removing at leastone selected section of the porous diffuser layer to uncover an area ofa major open end of a receptacle that the porous diffuser layerocclusively overlaid before being removed, to allow accelerated emissionof fragrance from that receptacle.

Embodiment 22 is the method of embodiment 21 wherein the methodcomprises sequential removal of selected sections of the porous diffuserlayer, the sequential removals being spaced over a period of at leastone day.

Embodiment 23 is the method of any of embodiments 21-22 wherein themethod comprises sequential removal of selected portions of theremovable cover sheet, the sequential removals being spaced over aperiod of at least one day.

Embodiment 24 is the method of any of embodiments 21-23 wherein thefragrance dispenser is positioned in a quiescent air environment in alocation chosen from the group consisting of an interior of a room of abuilding and an interior of a vehicle.

Embodiment 25 is the method of any of embodiments 21-23 wherein thefragrance dispenser is positioned in an airflow path in a locationchosen from a group consisting of a position proximate an air filter ofan HVAC system, a position proximate an air filter of a room airpurifier, a position proximate an air filter of a vehicle, a positionproximate a motorized fan, a position proximate an air vent of an HVACsystem, and a position proximate an air vent of a vehicleclimate-control system.

The present application is a continuation of U.S. patent applicationSer. No. 16/311,528, now allowed, which was a national stage filingunder 35 U.S.C. 371 of PCT application PCT/US2017/039400, which claimedpriority to U.S. Provisional Patent Application 62/356,668, thedisclosures of all of which are incorporated by reference in theirentirety herein.

It will be apparent to those skilled in the art that the specificexemplary elements, structures, features, details, configurations, etc.,that are disclosed herein can be modified and/or combined in numerousembodiments. All such variations and combinations are contemplated bythe inventor as being within the bounds of the conceived invention, notmerely those representative designs that were chosen to serve asexemplary illustrations. Thus, the scope of the present invention shouldnot be limited to the specific illustrative structures described herein,but rather extends at least to the structures described by the languageof the claims, and the equivalents of those structures. Any of theelements that are positively recited in this specification asalternatives may be explicitly included in the claims or excluded fromthe claims, in any combination as desired. Any of the elements orcombinations of elements that are recited in this specification inopen-ended language (e.g., comprise and derivatives thereof), areconsidered to additionally be recited in closed-ended language (e.g.,consist and derivatives thereof) and in partially closed-ended language(e.g., consist essentially, and derivatives thereof). Although varioustheories and possible mechanisms may have been discussed herein, in noevent should such discussions serve to limit the claimable subjectmatter. To the extent that there is any conflict or discrepancy betweenthis specification as written and the disclosure in any documentincorporated by reference herein, this specification as written willcontrol.

What is claimed is:
 1. A fragrance dispenser comprising: a basecomprising at least one receptacle with a major closed end and a majoropen end; a porous diffuser layer comprising at least one sectional areathat occlusively overlies at least a portion of a major open end of areceptacle; and, a fragrance source provided within at least a portionof the at least one receptacle and that comprises at least onevolatilizable fragrance, wherein the at least one sectional area of theporous diffuser layer is removable from remaining portions of the porousdiffuser layer to uncover at least a portion of a receptacle that the atleast one sectional area occlusively overlies.
 2. The fragrancedispenser of claim 1 wherein the porous diffuser layer is at leastsubstantially impermeable to liquids.
 3. The fragrance dispenser ofclaim 1 further comprising a secondary diffuser layer that: is at least50% more permeable to passage of fragrance therethrough than is theporous diffuser layer; does not comprise any removable sectional areas;and is sandwiched between the porous diffuser layer and the base,wherein the porous diffuser layer and the secondary diffuser layer areconfigured so that upon removal of a sectional area of the porousdiffuser layer, a portion of the secondary diffuser layer that overliesa receptacle of the base is exposed.
 4. The fragrance dispenser of claim3 wherein the secondary diffuser layer is chosen from the groupconsisting of a nonwoven organic polymeric web, a woven or knittedorganic polymeric mesh, and an organic polymeric netting or screen. 5.The fragrance dispenser of claim 1 wherein the base is made of athermoplastic organic polymeric resin that is at least substantiallyimpermeable to liquids and vapors and wherein each receptacle isprovided by a thermoformed depression in the base, wherein a terminus ofthe depression provides the major closed end of the receptacle andwherein a major open end of the depression provides the major open endof the receptacle.
 6. The fragrance dispenser of claim 1 wherein thefragrance source is chosen from the group consisting of neat liquidfragrance, liquid fragrance mixed with a nonvolatilizable diluentliquid, liquid fragrance in aqueous solution, and a liquid fragrancesorbed into interstices of a porous insoluble solid matrix material. 7.The fragrance dispenser of claim 1 wherein the fragrance source is aliquid fragrance that is mixed and solubilized with a nonvolatilizablematrix material that is a solid at room temperature and that issolublizable by the liquid fragrance, and wherein the fragrance-matrixmixture is in the form of a solid wafer when at 21° C.
 8. The fragrancedispenser of claim 1 wherein the liquid fragrance makes up from 80 wt. %to 100 wt. % of the fragrance source.
 9. The fragrance dispenser ofclaim 1 comprising: a base comprising a plurality of receptacles eachwith a major closed end and a major open end; a porous diffuser layercomprising sectional areas each of which occlusively overlies at least aportion of a major open end of a receptacle of the plurality ofreceptacles; and, a fragrance source provided within at least a portionof each receptacle and that comprises at least one volatilizablefragrance, wherein at least selected sectional areas of the porousdiffuser layer are each individually removable from the porous diffuserlayer to uncover at least a portion of a receptacle that the selectedsectional area occlusively overlies.
 10. The fragrance dispenser ofclaim 9 wherein the base comprises at least six receptacles and whereinthe porous diffuser layer comprises at least six sectional areas thatrespectively occlusively overlie at least a portion of a major open endof each of the six receptacles, which six sectional areas are eachfrangibly connected to remaining areas of the porous diffuser layer sothat the six sectional areas are each individually removable from theporous diffuser layer.
 11. The fragrance dispenser of claim 9 whereinthe major open end of each receptacle exhibits an area and wherein thesectional area of the porous diffuser layer that is individuallyremovable from the porous diffuser layer, is configured so that removalof the sectional area of the porous diffuser layer uncovers from about10% to about 100% of the area of the major open end of the receptaclethat the sectional area of the porous diffuser layer occlusivelyoverlies so as to allow accelerated emission of fragrance from thatreceptacle, while not allowing accelerated emission of fragrance fromany other receptacle.
 12. The fragrance dispenser of claim 9 wherein themajor open end of each receptacle exhibits an area and wherein asectional area of the porous diffuser layer that is individuallyremovable from the porous diffuser layer, is configured so that removalof the sectional area of the porous diffuser layer uncovers from about40% to about 60% of the area of the major open end of the receptaclethat the sectional area of the porous diffuser layer occlusivelyoverlies.
 13. The fragrance dispenser of claim 9 wherein theindividually removable sectional areas of the porous diffuser layer arefrangibly connected to remaining areas of the porous diffuser layer byfrangible connections that are provided by die cuts that extend throughthe entire thickness of the porous diffuser layer except at periodicbridging locations where the die cuts are interrupted to providefrangible bridges between the individually removable sectional areas ofthe porous diffuser layer and the remaining areas of the porous diffuserlayer.
 14. The fragrance dispenser of claim 13 wherein at least some ofthe periodic bridging locations are between adjacent edges ofindividually removable sectional areas of the porous diffuser layer. 15.The fragrance dispenser of claim 9 further comprising a removable coversheet that overlies, and is removably adhesively bonded to, the porousdiffuser layer; and, that comprises at least selected portions that arepeelably detachable from the porous diffuser layer to expose the porousdiffuser layer to initiate dispensing of the fragrance.
 16. Thefragrance dispenser of claim 15 wherein the dispenser comprises at leastone indicia printed on a major surface of the base, of the porousdiffuser layer, or of the removable cover sheet.
 17. A method ofdispensing fragrance into an atmosphere, the method comprising:positioning a fragrance dispenser of claim 1 in the atmosphere; if aremovable cover sheet is present, removing at least a selected portionof the removable cover sheet from the fragrance dispenser; and,optionally removing at least one selected section of the porous diffuserlayer to uncover an area of a major open end of a receptacle that theporous diffuser layer occlusively overlaid before being removed, toallow accelerated emission of fragrance from that receptacle.
 18. Themethod of claim 17 wherein the method comprises sequential removal ofselected sections of the porous diffuser layer, the sequential removalsbeing spaced over a period of at least one day.
 19. The method of claim17 wherein the fragrance dispenser is positioned in a quiescent airenvironment in a location chosen from the group consisting of aninterior of a room of a building and an interior of a vehicle.
 20. Themethod of claim 17 wherein the fragrance dispenser is positioned in anairflow path in a location chosen from a group consisting of a positionproximate an air filter of an HVAC system, a position proximate an airfilter of a room air purifier, a position proximate an air filter of avehicle, a position proximate a motorized fan, a position proximate anair vent of an HVAC system, and a position proximate an air vent of avehicle climate-control system.